Performing eight shows a week on Broadway is no part-time job, and yet many performers find time and energy on their days off (or hours off) to work in cabaret. There's obviously some overlap between the two disciplines, given that an actor might sing the same song on stage in a musical that they're including in their club act, but that's bound to be where the similarities end. You won't find a 30-piece orchestra in any nightclubs I know of. Even the largest rooms, like Joe's Pub, seat less than 200 people and many smaller ones, like The Duplex, max out well under 100. Still there's something special about singing directly to small group of people that keeps Broadway talent coming to the proverbial cabaret.

Telly Leung is currently starring in his fifth Broadway show, Allegiance. Over the years, he has performed many solo evenings concurrently with his Main Stem gigs, including a recent Joe's Pub concert to celebrate his second solo album, "Songs For You." Leung acknowledges the challenges of juggling two lines of work. "Singing eight times a week is a full-time job that requires being physically fit, a strict diet, continued vocal training, a disciplined sleep schedule and periods of silence for vocal recovery. If a show is vocally demanding, I won't do any late-night performing post-show. I go right to bed! That's certainly what I'm doing on Allegiance."

Other performers, like Kinky Boots' Kevin Smith Kirkwood, feel that a Broadway show is actually a great warmup for his club act, Classic Whitney, at The Cutting Room. "Singing my high, high tenor track in Kinky every night would definitely assure that I'm warmed up enough vocally to handle an hour of belting Whitney [Houston] tunes."

Kirkwood's Kinky Boots co-star Natalie Joy Johnson (who will debut her new club act, Natalie Joy Johnson and The Raging Case, at Joe's Pub Jan. 20) sees both sides of the issue. She spent the summer doing double duty with her Co Dependent Mondays show at Therapy in Hell's Kitchen. "I would run over after Kinky Boots still wearing my wig prep. It was divine — exhausting, but also exhilarating."

Leung longs for "the days of Merman and Rodgers and Hammerstein when musicals were written in manageable keys, so that performers could sing a show eight times a week and then do a late night club act!"

That is, unless you're Patti LuPone. Leung recalls LuPone's post-Evita concerts at Les Mouches calling her a "Broadway stamina goddess." "How did she do it?!" he marvels. Leung says he's only able to take on late-night gigs when he's in a show that is less vocally taxing — certainly playing Eva Peron wouldn't qualify.

Sylvia star Annaleigh Ashford shares this affection for the legacy of the Golden Age when Broadway stars coalesced into the late-night entertainment scene. She celebrated her new CD "Lost In The Stars" with a special New Year's Eve engagement at Feinstein's/54 Below. She, for one, would like to do a set that is an homage to those glory days.

While it may be demanding to do double-duty, Leung seems to represent a consensus when he notes the joy of taking on extra-curricular engagements. "[It] far outweighs being a little tired — and it's that kind of collaboration that makes me truly love what I do for a living," he says. He adds that the nakedness of performing in cabaret has made him a better actor. "It is scary to be up there with nothing but the voice, and trust that is enough. It requires complete presence, an ability to read a room's energy, and delivering material in a personal and honest way."

Ashford describes this intimacy as "an invisible string attached to you and the audience." "The room is so small and the material is often so personal, it's easy to feel that string and stay connected to it through the show," she says. "Cabaret has taught me to embrace that it's all a communal event whether it be for 150 or 1,150 people."

That difference in size of audience can also be a commercial asset for Broadway performers trying to sell tickets to their cabaret shows. Kirkwood has sold out at The Duplex and the Laurie Beechman Theatre for years, but credits his present work on the Great White Way for ensuring the success of Classic Whitney. "Performing in a Broadway hit opens up your [solo] audience to the fans of that show and also lends a certain 'legit' quality to your talent and brand," says Kirkwood.

Johnson points out, "Being in the Broadway community provides access to an audience already interested in the wares you're bringing to the table — songs, stories, and maybe a back-up dancer moment or two."

Whatever the obstacles, Broadway and cabaret go hand-in-hand. It's clear these people have all the talent — and want to exercise it — so long as they can find the time.